Health.com: 11 Ways to Boost Your Energy with Food

Eat More Iron from Plants

Certain nutrients, especially iron, may help women feel more energized. Nearly 10% of women between the ages of 20 and 49 are iron-deficient, which can cause fatigue and impair physical and mental endurance. Iron is needed to deliver oxygen to cells, and too little has also been shown to decrease immunity. A recent study found that over 10 years, women who consumed the most plant-based iron were 35% less likely to develop PMS than women who consumed the least. Great plant sources of iron include beans, lentils, spinach, and sesame seeds; eating them with vitamin C-rich foods can boost iron absorption.

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Feeling sluggish? Healthy fats, iron-rich foods, and smart snacking can help you fight fatigue. -By Amy O'Connor When Health asked what nutrition topic you need help with RIGHT NOW, the response was unanimous: eating for energy! You told us you feel run down and exhausted, and turn to sugar and/or caffeine to bolster flagging energy reserves. Bad idea, says Dina Aronson, RD: "Fatigue breaks us down physically and emotionally and wreaks havoc on the immune system, making us more susceptible to illness, depression, and even chronic conditions like heart disease." Moreover, proper nutrition and the timing of what you eat can do wonders to make you feel alert and powerful, says Cynthia Sass, RD, Health's nutrition and weight loss blogger. Here, new rules for eating for energy.

Certain nutrients, especially iron, may help women feel more energized. Nearly 10% of women between the ages of 20 and 49 are iron-deficient, which can cause fatigue and impair physical and mental endurance. Iron is needed to deliver oxygen to cells, and too little has also been shown to decrease immunity. A recent study found that over 10 years, women who consumed the most plant-based iron were 35% less likely to develop PMS than women who consumed the least. Great plant sources of iron include beans, lentils, spinach, and sesame seeds; eating them with vitamin C-rich foods can boost iron absorption.

Sass says the right formula for maximum energy is: fruit or veggie + a whole grain + lean protein + plant-based fat + herb/spice. She calls it the '5 piece puzzle' and it's the premise of her book S.A.S.S! Yourself Slim. "Balance is key; your body loves to be in balance," says Sass. "Giving it less of something it needs throws things off, as does giving it more than it needs."

Despite the health benefits of tea and coffee, if you're feeling run down, cut it out: "Caffeine gives a ‘false' energy essentially, because it's a stimulant," Sass says. "And after it peaks, you can start to feel tired or even more tired."

Don't limit your morning meal to protein or carbs; breakfast needs to be balanced too, Sass says. Instead of having just yogurt, add some high antioxidant fruit, a good fat like nuts or seeds, and raw or toasted oats. And go for organic nonfat yogurts to maximize protein and quality.

Real food means food that's closer to nature: whole grains rather than processed chips or crackers from a box, whole fruit rather than juice or fruit bars. The energy dividends will pay off! "When I've had clients swap more processed foods for ‘real' whole foods, their energy has gone through the roof, and many lose weight, even if the swaps result in eating more calories," Sass says.

Sass recommends eating a wide variety of Superfuits—apples, stone fruits, berries, tomatoes. Limiting yourself to the same old banana for breakfast curbs your nutrient and antioxidant intake and can make you feel run down. "Research shows that people who eat the same amount of produce but a wider variety have less oxidative stress, which is a precursor to aging and disease," she says.

When choosing an energy bar, ignore what's on the front of the package and check the ingredients list, says Sass: "If the ingredients read like a recipe, and I feel like I could buy the ingredients and make it myself, that's great. If it reads like a science experiment, with ingredients that aren't real whole foods, I'll pass, regardless of the protein/carb/fat ratio or vitamin/mineral content."

Don't eliminate healthy fats if you want more energy. "You need fat to absorb some key antioxidants," says Sass. In one study that compared salads served with fat-free, low-fat, and full-fat dressing, people absorbed fewer antioxidants from the veggies when they ate fat-free dressing. The reason: Some antioxidants have to grab onto fat in order to be absorbed from the gastrointestinal tract into the blood, where they can go to work. Antioxidants are important for energy because they flight free radicals and keep your cells healthy, Sass adds.

The secret to eating for energy, according to many nutritionists? Eat locally and in season. "When you go to your farmers market, a lot of times the produce was harvested less than 48 hours before you buy it, and because it didn't have to travel far, it was allowed to really reach its peak, which means more nutrients," Sass says.

While fresh and local is great, frozen foods are a potent source of energizing nutrients too. "Freezing actually locks in nutrients, so a frozen fruit with no added ingredients can be just as nutritious or even more than fresh, unless the fresh was just picked," Sass says. "The minute a fruit or veggie is harvested, it starts to lose nutrients."